With the help of Normanby's influence in the Whig ministry,
Adamson obtained the incumbency of Amherst Island, Upper Canada,[1] and
became the personal chaplain to Lord Sydenham,[2] and
tended to him until his death in 1841. Later that year, Adamson
became the Legislative
Council of the Province of Canada's chaplain and librarian. The
position was made a sinecure in 1851, and Adamson held it until
1867, when he became a Senate librarian. He only stayed there for a
few months, before resigning. Shortly afterward, Adamson died in Ottawa, Ontario on 7 August 1868.[1]

As a preacher, Adamson had been described as "one of the most
eloquent in North America". He was assistant to several churches,
including Christ Church Cathedral in
Montreal from 1844 to 1850, Holy Trinity Anglican
Cathedral in Quebec from 1851 to 1855, and again from 1861 to
1866, and St George's in Toronto, from 1856 to 1860.
He held the position of secretary at the Church Society of the
Diocese of Quebec, and lectured in the evenings at the Quebec
cathedral.[1] He
was also an occasional writer, focusing on subjects related to
sports and nature. His publications were found in the Dublin University
Magazine, Blackwood's Magazine, and
other British periodicals. He has also written articles for most
Canadian magazines of his time, including the article entitled "The
decrease, restoration, and preservation of salmon in Canada",
published in the Canadian Journal in 1857. As an avid
fisherman, Adamson wrote on the subject in his book
Salmon-fishing in Canada, published in 1860 by Sir James
Edward Alexander. Adamson has been described "the Izaak Walton of
Canada". The British Literary Gazette described
Adamson as someone who "is evidently, as all anglers should be, a
true lover of nature, and some of his descriptions of Canadian
scenery are given with considerable effect".[1]
Several universities awarded Adamson honorary Doctor of
Civil Law degrees, including McGill University and the University of Bishop’s College. He
was also noted as a powerful preacher; one publication called him
"one of the most eloquent in North America".[1]